Be it in the full, judging glare of the noonday sun, or as a clumsy altercations by flashlight at midnight,

He must find his way through the huddled crowd amassed atop his vessel, and, upon demand, turn himself into a human toilet.

This is a small but important task since (a) they can't allow the shipboard facilities to be overwhelmed by the sheer numbers, and (b) they can't have people defecating over the ship's edge as a matter of safety, and (c) they probably want to gather specimens from sick people.